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Decreased walking speed is associated with impaired physical performance and function in older adults. Following total ankle arthroplasty (TAA), walking speed continues to be slower than age matched controls. The purpose of this study was to determine if patients 1 year post-TAA can achieve walking speed benchmarks and investigate if gait metrics are predictive of achieved benchmarks. 191 TAA patients were recruited and assessed pre-TAA and 1 year post-TAA. Kinetic and kinematic data were collected during seven self-selected speed barefoot walking trials along a 30-m walkway. Receiver operator curves were generated for each variable to determine threshold values needed to achieve walking speeds of 0.8, 0.9, 1.1, and 1.3 m/s. Each variable's predictive ability was classified according to the area under the curve. Ninety one percent of participants achieved a walking speed 0.8 m/s, 85.3% achieved ≥0.9 m/s, 64.9% walked at ≥1.1 m/s, and 24.1% achieved a walking speed of 1.3 m/s by 1 year post-TAA. Walking speed pre-TAA was the strongest predictor with ankle moment, power and GRF data showing mixed results. Clinical Significance: 75.9% of participants were unable to walk at 1.3 m/s-a speed indicative of safely crossing a street. Variables predictive of postoperative walking speed benchmarks could be useful in developing interventions for the TAA population. The strongest predictor across all walking speed benchmarks was preoperative walking speed. A walking speed 0.71 m/s was predictive of achieving 0.8 m/s 1 year post-TAA, while1.09 m/s predicted 1.3 m/s 1 year post-TAA.

Hop tests are widely used to quantify recovery from anterior cruciate ligament reconstruction (ACLR) surgery. However, there is evidence that simply measuring hop distance may not be indicative of the quality of movement or representative of potential limitations in hopping mechanics, particularly during landing. The first purpose of the present study was to compare hop distance and loading symmetry between ACLR athletes and healthy uninjured recreational athletes. The second was to determine the association between hop distance and loading symmetry.Twenty-five ACLR patients and 30 healthy controls completed the single hop, triple hop, and crossover hop test on each limb while the loadsol®, a single-sensor force insole, collected impact forces (100 Hz). A limb symmetry index (LSI) was calculated for hop distance, peak impact force, loading rate, and impulse from the final landing of each trial. LSI values were compared between groups using Mann-Whitney U tests, and distance and loading LSI values were compared using Spearman rank correlations.ACLR patients had reduced symmetry in hop distance and loading relative to healthy controls for every hop test and outcome measure (P0.05), except peak impact force on the single hop. Hop distance symmetry was significantly related to each loading symmetry measure on the crossover hop test (P0.01) and to peak impact force and impulse symmetry on the single hop test (P0.05) in each group.This study demonstrates that ACLR patients both hop further and generate larger forces when hopping on their nonsurgical limb relative to their surgical limb. In addition, hop distance and loading symmetry provide clinicians and researchers with different information and therefore should be considered together when making return to sport decisions.

Changes in running gait may contribute to injury risk, but currently this research is restricted to lab settings due to limitations with currently available and used technology. Purpose The purpose of this study was to determine if peak ground reaction force (GRF), loading rate (LR) and impulse metrics change across an outdoor run using force sensing insoles. We hypothesize that over the course of the run there would be a decline in limb symmetry for all measures and a decrease in LR and GRF values. Methods 30 healthy participants (15 male, 15 female) were recruited for a 2 visit study during which a 2 or 4 mile run was completed on the first visit and the other run distance was completed on the second visit (order was randomized). Force data was collected at 100Hz for the duration of the run. Peak GRF, impulse, LR and limb symmetry indices (LSI) of these variables were calculated at 25%, 50%, and 75% of the run. Results GRF decreased over the course of the runs, but the GRF LSI remained unchanged. No changes in LR were detected over the 2 or 4mi run for either limb. The impulse LSI during the 2mi run did indicate decreased symmetry from 25% of the run to 50% of the run the LR LSI improved and there was no difference in GRF LSI or any of the LSI metrics during the 4mi run. Conclusion: We posit that the lack in change in LSI was due to the courses/distance not inducing fatigue in our population. Future studies should investigate the impact of outdoor fatigue protocols and various types of terrain on force metrics and potential injury risk factors.

Background Previous studies have demonstrated differences in gait speed and ground reaction forces (GRF) based on age as well as sex during lab-based testing. With advancements in wearable technology, it may be possible to assess differences in loading parameters in non-lab settings using portable data collection methods. Research question The purpose of this study is to determine if wearable sensors (loadsol®) are valid for assessing peak force, impulse and loading rate (LR) in older adults and determine if the insole can detect sex and age differences in these parameters during walking. Methods Twenty young (22.2 ± 2.9 years) and 23 older adults (68.1 ± 5.8 years) walked at a self-selected speed on a flat, inclined and declined instrumented treadmill (randomized order). Force data was simultaneously collected from the treadmill (1440 Hz) and insoles (100 Hz) during each condition. To assess validity, an ICC(3,k) and a Bland-Altman plot was generated for each variable and condition in the older adults. To determine age and gender differences, an ANCOVA (covary: walking speed) was completed for each variable. Results All ICCs were greater than 0.88 for vGRF, impulse and loading rate. The Bland-Altman plots report a bias of less than 2% for vGRF, -8 to -15 % for impulse and -5 to 2% for loading rate. The ANCOVA results indicate that the loadsol® has the ability to detect differences between age groups in peak vGRF in the flat, declined and inclined conditions which are in agreement with the differences the force plates detected. Similarly, the loadsol® and force plates agreed with age-based differences in the flat and inclined condition, but the loadsol® missed the declined LR difference. Significance The ability to collect data in nontraditional settings has the potential to broaden the research questions investigated, explore clinical applications and increase the generalizability.

Hyaluronan (HA), a high molecular weight non-sulfated glycosaminoglycan, is an integral component of the extracellular matrix of developing and mature connective tissues including tendon. There are few published reports quantifying HA content during tendon growth and maturation, or detailing its effects on the mechanical properties of the tendon extracellular matrix. Therefore, the goal of the current study was to examine the role of HA synthesis during post-natal skeletal growth and maturation, and its influence on tendon structure and biomechanical function. For this purpose, the morphological, biochemical, and mechanical properties of Achilles tendons from wild type (WT) and hyaluronan synthase 1 and 3 deficient mouse strains (Has1-/- (Has1KO), Has3-/- (Has3KO), and Has1-/- 3-/- (Has1/3KO)) were determined at 4, 8, and 12 weeks of age. Overall, HAS-deficient mice did not show any marked differences from WT mice in Achilles tendon morphology or in the HA and chondroitin/dermatan sulfate (CS/DS) contents. However, HAS1-deficiency (in the single or Has1/3 double KO) impeded post-natal formation of the retrocalcaneal bursa, implicating HAS1 in regulating HA metabolism by cells lining the bursal cavity. Together, these data suggest that HA metabolism via HAS1 and HAS3 does not markedly influence the extracellular matrix structure or function of the tendon body, but plays a role in the formation/maintenance of peritendinous bursa. Additional studies are warranted to elucidate the relationship of HA and CS/DS metabolism to tendon healing and repair in vivo. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2622-2632, 2018.

There is limited literature that follows a population of Anterior Cruciate Ligament Reconstruction (ACLR) patients through recovery. Our aim was to examine differences in movement and loading patterns across time and between limbs over four visits during 12 months post-ACLR. We hypothesized that kinematic and kinetic data during a stop-jump would have time- and limb-dependent differences through 12 months post-surgery. Twenty-three ACLR athletes performed five vertical stop-jumps at 4, 5, 6, and 12 months post-op with motion capture and force plate data collection. The peak knee flexion (PKF) was different between the 4 and 12, 5 and 6, and the 5 and 12 month visits with earlier months exhibiting higher PKF. The peak vertical ground reaction force (vGRF) was lower at 4 than at 5 and 6 months. The peak posterior ground reaction force (pGRF) was lower at 4 months than all other visits. Frontal knee and sagittal hip range of motion (ROM) were different between 12 months and each previous visit. Asymmetries were present in peak vGRF, peak knee extension moment and impulse up to 12 months. The loading rate and peak pGRF demonstrated between limb differences up to 6 months; limb stiffness demonstrated differences up to 5 months post-ACLR. PKF was only asymmetric at the 4 month visit. While some variables improved in the 12 months post-ACLR, limb asymmetries in peak knee extension moment, peak vGRF and impulse persisted up to 12 months. Additionally, frontal plane knee and sagittal hip ROM had not normalized at 12 months. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1887-1893, 2018.

The assessment of loading during walking and running has historically been limited to data collection in laboratory settings or with devices that require a computer connection. This study aims to determine if the loadsol®—a single sensor wireless insole—is a valid and reliable method of assessing force. Thirty (17 male and 13 female) recreationally active individuals were recruited for a two visit study where they walked (1.3 m/s) and ran (3.0 and 3.5 m/s) at a 0%, 10% incline, and 10% decline, with the visits approximately one week apart. Ground reaction force data was collected on an instrumented treadmill (1440 Hz) and with the loadsol® (100 Hz). Ten individuals completed the day 1 protocol with a newer 200 Hz loadsol®. Intraclass correlation coefficients (ICC3,k) were used to assess validity and reliability and Bland–Altman plots were generated to better understand loadsol® validity. Across conditions, the peak force ICCs ranged from 0.78 to 0.97, which increased to 0.84–0.99 with the 200 Hz insoles. Similarly, the loading rate ICCs improved from 0.61 to 0.97 to 0.80–0.96 and impulse improved from 0.61 to 0.97 to 0.90–0.97. The 200 Hz insoles may be needed for loading rate and impulse in running. For both walking and running, the loadsol® has excellent between-day reliability (>0.76). Published version

This dissertation explores the representation of maternity in two of Boccaccio's works, the early idyllic poem, the Ninfale fiesolano, and the author's later magnum opus, the Decameron, through readings in the social history of women and the family and medieval medical literature of obstetrics and gynecology. I create a dense historical context from which to examine the depiction of generative processes, maternity, and mother-child interactions in these works, allowing us to better understand the relationship between Boccaccio's treatment of these subjects and the author's larger stance on women and gender. In Chapter One, I explore Boccaccio's uncommon interest in the events between conception and birth in the Ninfale fiesolano; I demonstrate the conformity of the Ninfale's literary depictions of conception, pregnancy, and childbirth to the medical literature of obstetrics and gynecology and social practices in the late Middle Ages. In the second chapter, I explore how the Ninfale, traditionally seen as an idyllic, mythological poem, reflects the practices and ideologies of the normative form of family structure in fourteenth-century Tuscany, the patrilineage. I first show how the poem's pervasive discourse on resemblance exposes, and undercuts, the importance of the paternal line; I then consider how Mensola's joyful maternity - her beautifully rendered interactions with baby Pruneo - contains an implicit critique of the role and function of maternity in patrilineal society. With Chapter Three, I turn to Boccaccio's prose works; I explore how Boccaccio incorporates specific and historicized beliefs about generative physiology - the biological pre-conditions for maternity - into commonplaces of the misogynistic tradition in the Corbaccio and Decameron V.10. Chapters Four and Five focus specifically on the Decameron. In the fourth chapter, I consider how Boccaccio uses a distinctly gendered language of generation in Decameron III.8, V.7, X.4, and, most spectacularly, X.10 to underscore the marginality of women to family and line. In the fifth, and final, chapter, I explore the profound cultural embeddedness of Boccaccio's treatment of maternity by placing the Decameron's depictions of motherhood - whether unwanted, farcical, or affective - within the greater social context of Renaissance natalism. Throughout this project, I consider how representations of maternity and generative processes in Boccaccio's texts comment on the realities of motherhood - and womanhood - in the patrilineal society of fourteenth-century Tuscany.